According to MacLysaght, there were several families whose Irish Gaelic surname was anglicized 'Curran'. It would depend on whether they lived in:
A good resource would be Rev. Woulfe's "Irish Names and Surnames" as he gives the original spellings of the various Curran families. It's online at google books.
In Irish Gaelic it is diabéiteas.
Irish Gaelic: Feirmeoir.Scottish Gaelic: Tuathanach.
In the Irish, Roibeard; in the Scottish Gaelic, Raibeart.
"Gaelic" can mean "Irish Gaelic' or "Scottish Gaelic". They are classified as two distinct languages.
In Scottish Gaelic: Albannach In Irish Gaelic: Albanach
In Irish Gaelic: cuimhní In Scottish Gaelic: cuimhneachaidh
muirScottish Gaelic: muir Irish Gaelic: muir or farraige
silíni
dáthúil
Fíor
Gaige
Brioscú